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Version: Nightly

Prevent Metadata Changes

To prevent metadata changes, you can pause the procedure manager. This mechanism rejects all new procedures (i.e., new metadata-changing operations) while allowing existing procedures to continue running. Once enabled, the Metasrv will reject the following procedures:

DDL procedures:

  • Create table
  • Drop table
  • Alter table
  • Create database
  • Drop database
  • Create view
  • Create flow
  • Drop flow

Region procedures:

  • Region Migration
  • Region Failover (if enabled)
  • Auto Balancing (if enabled)

You may see error messages if you or Metasrv try to perform these procedures after metadata changes are paused. For region procedures, you can enable Cluster Maintenance Mode to temporarily disable them.

Managing procedure manager​

The procedure manager can be paused and resumed through Metasrv's HTTP interface at: http://{METASRV}:{RPC_PORT}/admin/procedure-manager/pause and http://{METASRV}:{RPC_PORT}/admin/procedure-manager/resume. Note that this interface listens on Metasrv's RPC_PORT, which defaults to 3002.

Pause Procedure Manager​

Pause procedure manager by sending a POST request to the /admin/procedure-manager/pause endpoint.

curl -X POST 'http://localhost:3002/admin/procedure-manager/pause'

The expected output is:

{"status":"paused"}

Resume Procedure Manager​

Resume procedure manager by sending a POST request to the /admin/procedure-manager/resume endpoint.

curl -X POST 'http://localhost:3002/admin/procedure-manager/resume'

The expected output is:

{"status":"running"}

Check Procedure Manager Status​

Check procedure manager status by sending a GET request to the /admin/procedure-manager/status endpoint.

curl -X GET 'http://localhost:3002/admin/procedure-manager/status'

The expected output is:

{"status":"running"}